What type of problems can you have with conformal coating?

Normally, when I am working with customers I see two types of problems.

Those are problems relating to the conformal coating process and those relating to the actual product reliability.

They are two very different issues to deal with.

Conformal coating reliability problems

Ultimately, there are many factors that can affect the short, medium and long-term reliability of a circuit board.

It is not just the conformal coating that can influence this.

However, if the conformal coating material is not correctly specified at the reliability design stage then this could be the major issue and the reason for failure.

Once the product reliability requirements have been defined as part of the conformal coating design procedure then the resulting information needs to be combined with the data from the conformal coating holistic approach.

This will ensure that the risks of a failure due to the conformal coating are minimised.

if the conformal coating material is not correctly specified at the reliability design stage then this could be the major issue and the reason for failure.
If the conformal coating material is not correctly specified at the reliability design stage then this could be the major issue and the reason for failure.

Conformal coating process problems

Typical failure mechanisms in conformal coating processing normally come from the conformal coating masking process or the application process.

Conformal coating masking failures

Failures in the masking process are generally a known quantity and easy to understand.

Adopting best practice methods for conformal coating masking can help to minimise these problems.

Masking with tape and latex 1 600
Using best masking techniques can minimise some problems found in conformal coating processing

Conformal coating application failures

Failures in the conformal coating application process are very well understood.

Typical failure mechanisms include:

  • Bubbles
  • Blushing
  • Contamination
  • Capillary Flow
  • Orange Peel
  • Shadowing
  • Cracking
  • Delamination
  • De-wetting
  • Fish Eyes

Understanding and troubleshooting why these conformal coating failures occur can quickly lead to a solution to the failure in the conformal coating process.


Need help with your conformal coating process?

Contact Nexus now and let us show you how we can help you.


Dr Lee Hitchens, Author of Nexus website and ebook

Dr Lee Hitchens is the Author of the Nexus eBook and a main contributor to Nexus.

 

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Read Part 3 of our Series, “Key fundamental challenges in conformal coating production” on how process control affects the line

Conformal Coated Circuit BoardPart 3 of this series of articles is launched this week where Dr Lee Hitchens examines how process control influences the production line.

Nexus has highlighted six critical areas that affect coating production and reduce performance on the line. These are the machines, materials, staff, process control, upstream processes and customer requirements.

In a series of six articles over the six weeks Nexus will attempt to highlight these six key areas and how the production line can be improved to achieve acceptable levels of defects.

Click here to Find out more…..

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Machines in Conformal Coating and How they affect Production

Conformal Coating Bubble defectsArticle by Dr Lee Hitchens

When I am asked to examine a conformal coating production line, and give my opinion on its effectiveness to produce the right work, I can be confronted with a wide range of setups. This can be from the most basic robotic system that coats a simple pattern and the operator has to control all the variables. Or, it can be a state of the art system with every known option present ultimately attempting to control the machine process. I say attempt because ultimately we are dealing with conformal coating liquids, people and the production environment. These are variables that affect the ability of the machine to do its job effectively and completely dependent on each of these factors.

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Find out more about Joining Nexus by Clicking Here….

This article is one of six of the series, “What are the Key Fundamental Challenges in Conformal Coating Production to help you achieve Acceptable Production Targets?”

Conformal coating production is like any other part of the process. There are key fundamental challenges to be met to ensure targets and acceptable defect rates are set. However, understanding the variables that affect production and how these contribute to poor coating performance is critical to ensuring a high quality, efficient coating process.

Nexus has highlighted six critical areas that affect coating production and reduce performance on the line. These are the machines, materials, staff, process control, upstream processes and customer requirements.

In a series of six articles Nexus will attempt to highlight these six key areas for production and how the production line can be improved to achieve acceptable levels of defects.

To Read More Click Here….